Jurgen Klopp's men produced some thrilling football at home to initially move 5-0 ahead, before Roma gave themselves a slight glimmer of hope with two surprise away goals.
Roma endured a curious first leg at Anfield having dominated the opening 20 minutes, only to be undone by some attacking brilliance as Liverpool moved into a 5-0 lead. The club's two surprise away goals will serve as a boost going into the second leg, but Eusebio Di Francesco's side are now requiring a second miracle in a month.
The Italian side have already demonstrated their abilities at the Stadio Olimpico, where they produced a thrilling 3-0 win over Barcelona to write off a 4-1 Catalan victory in the first leg in order to progress into the last four on away goals.
The defeat at Anfield saw the Rome club fall to their fourth straight loss in away matches in the Champions League, and they will now be relying on the cauldron of the Olimpico to try to put some pressure on the travelling Reds.
Klopp's men will be heading to a venue where Roma have not conceded in five Champions League games this season. Roma have already beaten the likes of Barcelona, Chelsea and Shakhtar Donetsk at home in the tournament across the group and knockout stages.
Roma president Jim Pallotta has been vocal following the incident in which a Reds fan was left in a critical condition, and has called for times to change as the incident brought the club into disrepute. Pallotta described the attack before the game at Anfield as displaying "most disgusting stupidity".
Edin Dzeko continues to be Roma's most prolific frontman both domestically and in the Champions League. The former Manchester City forward bagged one of Roma's away goals last week with a clinical finish. Diego Perotti scored a crucial penalty at Anfield too, although the playmaker has since picked up another frustrating knock and will probably sit out of the return leg.
Domestically, Di Francesco was forced to play a Roma side not too far off full strength at the weekend as they aim to secure a Champions League finish in Serie A. Dzeko, Patrik Schick and Stephan El Shaarawy were all on the scoresheet as the 10-man hosts overcame Chievo 4-1. The result keeps Roma in fourth place level on points with third-placed Lazio.
For all of the steel on display against Barca, Roma fans will be wary of the kind of performances the Giallorossi turned in when they were beaten by the likes of Sampdoria, AC Milan and Fiorentina, who have all come away with victories from the Olimpico this year.
Recent form: DLDWWW
Recent form (all competitions): WDWWLW
Klopp's Liverpool head to Roma standing on the brink of a first Champions League final appearance since 2007, when they lost out to AC Milan at the Olympic Stadium in Athens.
The Reds hold a 5-2 lead over Di Francesco's charges following a triumphant display at Anfield last week, although Roma might just be heading into the return leg with some momentum.
Liverpool will have in mind the comeback Roma pulled off against Barcelona in the quarters, but having rested a number of key men at the weekend the Reds head to Italy with a three-goal advantage and a fairly fresh squad aiming to get the job done.
For all of the on-field positivity, some worryingly ugly scenes plagued the first tie when a Reds fan was attacked by two men from Rome, leading to key conversations taking place between authorities, fans and football clubs ahead of Liverpool followers making the trip to the continent.
Klopp has been able to produce some wonderful showings in the Champions League this term, although the German coach has recently been split from his right-hand man Zeljko Buvac, who will be spending time away from the first team until the end of the season for personal reasons. Some speculation in the press had claimed that Buvac was to depart after falling out with Klopp, but the club has dismissed the claims. The pair have worked together for the past 17 years.
Liverpool rested players before facing Roma at Anfield and they were forced to draw 2-2 with West Bromwich Albion, and the same fate occurred this weekend when Klopp's men struggled to find a way past Stoke City at Anfield having drawn 0-0.
Salah was unable to score at the weekend but the Egyptian will surely be relishing the opportunity of heading back to the Stadio Olimpico having pushed Liverpool into an important lead in the tie. The 25-year-old scored 32 times for Roma before heading to Merseyside, where he now has 41 goals during his first season at the Reds.
Heading to Rome, Liverpool are now unbeaten in 15 Champions League fixtures and have scored at least two goals in eight of their last nine matches in the tournament. Another goal or two in Italy would surely take the contest beyond the sort of miracles even Roma have experienced.
Recent form: WWDWDD
Recent form (all competitions): DWWDWD
Di Francesco has already insisted that Perotti is likely to miss two weeks of football with another injury issue, while Kevin Strootman has also been listed as doubtful for Wednesday's game in Rome.
Dzeko is expected to continue in attack for Roma and Schick could join him later in the game. Kostas Manolas, Cengiz Under and Alessandro Florenzi were rested at the weekend and should all return for the visit of Liverpool.
Roma possible starting lineup:
Alisson; Fazio, Manolas, Jesus; Florenzi, De Rossi, Gonalons, Kolarov; Under, Nainggolan, Dzeko
Liverpool possible starting lineup:
Karius; Alexander-Arnold, Lovren, van Dijk, Roberts; Milner, Henderson, Wijnaldum; Mane, Firmino, Salah
Head To Head
Prior to last week's victory, the sides previously met in the second group stages of the Champions League in the 2001-02 season. Liverpool drew 0-0 away in Rome, before winning 2-0 in the reverse fixture back at Anfield.
Across European tournaments, these teams have played each other six times. Liverpool have now won three, drawn two and lost one against the Italians.
Before the 5-2 victory at Anfield, the club's most memorable meeting arguably came in the 1984 European Cup final, when Liverpool beat Roma to the crown with a with 4-2 win on penalties at the Stadio Olimpico.
We say: Roma 1-2 Liverpool
Liverpool hold a three-goal lead ahead of Wednesday's game and the club are now on the brink of equalling Barcelona's all-time record for goals in a single Champions League season. The Reds need just one goal in Rome to equal the Catalan side's total of 45 set in 1999-2000.
That run displays the sort of threat Klopp's men possess going forward, and they will be feeling confident of grabbing a vital goal or two that would ultimately kill this tie and send them into the final in Kiev.
Roma have already showcased that they are capable of pulling off the unthinkable, especially when playing at the potentially-hostile Olimpico. Should Strootman and Perotti miss out, though, the task will likely become even more monumental for Di Francesco's side.
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